The present invention relates generally to dynamoelectric machines. More specifically, this invention relates to an apparatus and method for forming a stator winding for a dynamoelectric machine into a desired shape.
A dynamoelectric machine, such as an electric motor, an electric generator, or a vehicle alternator, contains, among other things, a stationary component known as a “stator,” and a rotating component known as a “rotor.” In the most common embodiment, the perimeter of the rotor and an inside configuration of the stator are cylindrical in shape. It is known in the art that a stator and a rotor each may be manufactured from a core made from a magnetic material, around which or within which insulated electrical conductors known as “windings” or “coils” are installed.
A typical stator of a design known in the art comprises a hollow, cylindrical core, the inner surface of which contains slots, which extend the full length of the core parallel to the axial direction of the core. The portions of the stator core between the slots are known as the “teeth.” These teeth extend radially inward toward the center of the core.
Stator windings, commonly formed from insulated conductors of, for example, copper, comprise slot sections and end turns, with the slot sections being disposed in the stator slots and the end turns traversing a distance between sequential slot sections. Multiple layers of slot sections are disposed in each stator slot until a desired stator fill is achieved. It is desirable to maximize an amount of conductor within each stator slot, therefore the stator windings must be formed and placed on the stator core such that the layers nest together minimizing and gaps between layers in the stator slots. To promote the nesting of the various layers together, it is desirable to form the end turns to a precise shape, without damaging the conductor insulation during the forming process.